Who are the darkest, most disturbing characters in opera? After visiting the opera twice last week, I’ve got a couple of contenders. Duke Bluebeard with his castle of grisly secrets, and Wozzeck in all his murderous madness. Could the anti-heroes of, respectively, Bartók’s 1918 and Berg’s 1925 masterpieces, be two of the most unsettling characters out there? I certainly left both productions in a shocked daze.

Wozzeck, which I saw in the faded grandeur of Bristol’s Hippodrome when Welsh National Opera popped over the border last week, is an opera that’s hard to walk away cheerful from. For a start there’s the betrayal of Wozzeck by his lover Marie, swiftly leading on to jealousy, madness and murder. He is, as the WNO website helpfully points out, ‘doomed from birth – condemned to live in a brutal and loveless world.’

And Wozzeck isn’t simply a heartless murderer. The bleak reality of his day-to-day existence, his role as a victim of the bullying Captain, and as a scientific guinea pig for the Doctor, all play their part in destroying him – a poor man, ostensibly trying to do his best. Disturbed, certainly, but perhaps not a serious contender to be crowned opera’s most despicable, disturbing character.

Duke Bluebeard, on the other hand, is harder to feel compassion for. Especially in the gripping, if gruesome, production of Bartók’s only opera currently running at English National Opera. Under the direction of Daniel Kramer, the dark legend of Duke Bluebeard’s Castle becomes mixed with modern-day reality: here Bluebeard is a Josef Fritzl-like character with a family hidden away under lock and key, wives incarcerated for years on end.

As Judith – Bluebeard’s latest conquest – successively opens each of the seven doors to reveal Bluebeard’s bloody past, all you want to do is scream leave now, get out while you can. But, of course, she doesn’t. The opera progresses to its bloody end, with this Bluebeard revealing himself to be viler, more despicable, and more unhinged than you’d want to imagine.

Clearly this portrayal of Bluebeard owes as much, if not more, to the producer as Bartók, but how legitimate is it to make operas topical in this way? And is Bluebeard as Bartók created him as, less, or more disturbing than Kramer's Bluebeard?

Rebecca Franks is online editor and staff writer for BBC Music Magazine.